#include "opencv2/opencv.hpp"
#include "grabcut.hpp"
#include <iostream>

using namespace std;
using namespace cv;

static void help(char **argv)
{
    cout << "\nThis program demonstrates CGApply segmentation -- select an object in a region\n"
            "and then grabcut will attempt to segment it out.\n"
            "Call:\n"
         << argv[0] << " <image_name>\n"
                       "\nSelect a rectangular area around the object you want to segment\n" <<
         "\nHot keys: \n"
         "\tESC - quit the program\n"
         "\tr - restore the original img\n"
         "\tn - next iteration\n"
         "\n"
         "\tleft mouse button - set rectangle\n"
         "\n"
         "\tCTRL+left mouse button - set GC_BGD pixels\n"
         "\tSHIFT+left mouse button - set GC_FGD pixels\n"
         "\n"
         "\tCTRL+right mouse button - set GC_PR_BGD pixels\n"
         "\tSHIFT+right mouse button - set GC_PR_FGD pixels\n" << endl;
}

const Scalar RED = Scalar(0, 0, 255);
const Scalar PINK = Scalar(230, 130, 255);
const Scalar BLUE = Scalar(255, 0, 0);
const Scalar LIGHTBLUE = Scalar(255, 255, 160);
const Scalar GREEN = Scalar(0, 255, 0);

const int BGD_KEY = EVENT_FLAG_CTRLKEY;
const int FGD_KEY = EVENT_FLAG_SHIFTKEY;

static void getBinMask(const Mat &comMask, Mat &binMask)
{
    binMask = comMask & 1;
}

class GCApplication
{
public:
    enum
    {
        NOT_SET = 0, IN_PROCESS = 1, SET = 2
    };
    static const int radius = 2;
    static const int thickness = -1;

    void reset();

    void setImageAndWinName(const Mat &_image, const string &_winName);

    void showImage() const;

    void mouseClick(int event, int x, int y, int flags, void *param);

    int nextIter();

    int getIterCount() const
    { return iterCount; }

private:
    void setRectInMask();

    void setLblsInMask(int flags, Point p, bool isPr);

    const string *winName;
    const Mat *image;
    Mat mask;
    Mat bgdModel, fgdModel;

    uchar rectState, lblsState, prLblsState;
    bool isInitialized;

    Rect rect;
    vector<Point> fgdPxls, bgdPxls, prFgdPxls, prBgdPxls;
    int iterCount;
};

void GCApplication::reset()
{
    if (!mask.empty())
        mask.setTo(Scalar::all(GC_BGD));
    bgdPxls.clear();
    fgdPxls.clear();
    prBgdPxls.clear();
    prFgdPxls.clear();

    isInitialized = false;
    rectState = NOT_SET;
    lblsState = NOT_SET;
    prLblsState = NOT_SET;
    iterCount = 0;
}

void GCApplication::setImageAndWinName(const Mat &_image, const string &_winName)
{
    if (_image.empty() || _winName.empty())
        return;
    image = &_image;
    winName = &_winName;
    mask.create(image->size(), CV_8UC1);
    reset();
}

void GCApplication::showImage() const
{
    if (image->empty() || winName->empty())
        return;

    Mat res;
    Mat binMask;
    if (!isInitialized)
        image->copyTo(res);
    else
    {
        getBinMask(mask, binMask);
        std::cout << "----mask" << std::endl;
        std::cout << mask << std::endl;
        std::cout << "====binmask" << std::endl;
        std::cout << binMask << std::endl;
        image->copyTo(res, binMask);
    }

    vector<Point>::const_iterator it;
    for (it = bgdPxls.begin(); it != bgdPxls.end(); ++it)
        circle(res, *it, radius, BLUE, thickness);
    for (it = fgdPxls.begin(); it != fgdPxls.end(); ++it)
        circle(res, *it, radius, RED, thickness);
    for (it = prBgdPxls.begin(); it != prBgdPxls.end(); ++it)
        circle(res, *it, radius, LIGHTBLUE, thickness);
    for (it = prFgdPxls.begin(); it != prFgdPxls.end(); ++it)
        circle(res, *it, radius, PINK, thickness);

    if (rectState == IN_PROCESS || rectState == SET)
        rectangle(res, Point(rect.x, rect.y), Point(rect.x + rect.width, rect.y + rect.height), GREEN, 2);

    imshow(*winName, res);
}

void GCApplication::setRectInMask()
{
    CV_Assert(!mask.empty());
    mask.setTo(GC_BGD);
    rect.x = max(0, rect.x);
    rect.y = max(0, rect.y);
    rect.width = min(rect.width, image->cols - rect.x);
    rect.height = min(rect.height, image->rows - rect.y);
    (mask(rect)).setTo(Scalar(GC_PR_FGD));
}

void GCApplication::setLblsInMask(int flags, Point p, bool isPr)
{
    vector<Point> *bpxls, *fpxls;
    uchar bvalue, fvalue;
    if (!isPr)
    {
        bpxls = &bgdPxls;
        fpxls = &fgdPxls;
        bvalue = GC_BGD;
        fvalue = GC_FGD;
    } else
    {
        bpxls = &prBgdPxls;
        fpxls = &prFgdPxls;
        bvalue = GC_PR_BGD;
        fvalue = GC_PR_FGD;
    }
    if (flags & BGD_KEY)
    {
        bpxls->push_back(p);
        circle(mask, p, radius, bvalue, thickness);
    }
    if (flags & FGD_KEY)
    {
        fpxls->push_back(p);
        circle(mask, p, radius, fvalue, thickness);
    }
}

void GCApplication::mouseClick(int event, int x, int y, int flags, void *)
{
    // TODO add bad args check
    switch (event)
    {
        case EVENT_LBUTTONDOWN: // set rect or GC_BGD(GC_FGD) labels
        {
            bool isb = (flags & BGD_KEY) != 0,
                    isf = (flags & FGD_KEY) != 0;
            if (rectState == NOT_SET && !isb && !isf)
            {
                rectState = IN_PROCESS;
                rect = Rect(x, y, 1, 1);
            }
            if ((isb || isf) && rectState == SET)
                lblsState = IN_PROCESS;
        }
            break;
        case EVENT_RBUTTONDOWN: // set GC_PR_BGD(GC_PR_FGD) labels
        {
            bool isb = (flags & BGD_KEY) != 0,
                    isf = (flags & FGD_KEY) != 0;
            if ((isb || isf) && rectState == SET)
                prLblsState = IN_PROCESS;
        }
            break;
        case EVENT_LBUTTONUP:
            if (rectState == IN_PROCESS)
            {
                rect = Rect(Point(rect.x, rect.y), Point(x, y));
                rectState = SET;
                setRectInMask();
                CV_Assert(bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty());
                showImage();
            }
            if (lblsState == IN_PROCESS)
            {
                setLblsInMask(flags, Point(x, y), false);
                lblsState = SET;
                showImage();
            }
            break;
        case EVENT_RBUTTONUP:
            if (prLblsState == IN_PROCESS)
            {
                setLblsInMask(flags, Point(x, y), true);
                prLblsState = SET;
                showImage();
            }
            break;
        case EVENT_MOUSEMOVE:
            if (rectState == IN_PROCESS)
            {
                rect = Rect(Point(rect.x, rect.y), Point(x, y));
                CV_Assert(bgdPxls.empty() && fgdPxls.empty() && prBgdPxls.empty() && prFgdPxls.empty());
                showImage();
            } else if (lblsState == IN_PROCESS)
            {
                setLblsInMask(flags, Point(x, y), false);
                showImage();
            } else if (prLblsState == IN_PROCESS)
            {
                setLblsInMask(flags, Point(x, y), true);
                showImage();
            }
            break;
    }
}

int GCApplication::nextIter()
{
    std::cout << "in mask:" << mask << std::endl;

    if (isInitialized)
    {
        selfGrabCut(*image, mask, rect, bgdModel, fgdModel, 1);
        std::cout << "mask:" << mask << std::endl;
    } else
    {
        if (rectState != SET)
            return iterCount;

        if (lblsState == SET || prLblsState == SET)
        {
            selfGrabCut(*image, mask, rect, bgdModel, fgdModel, 1);
            std::cout << "set" << std::endl;
            std::cout << "mask:" << mask << std::endl;
        } else
            selfGrabCut(*image, mask, rect, bgdModel, fgdModel, 1);

        isInitialized = true;
    }
    iterCount++;

    bgdPxls.clear();
    fgdPxls.clear();
    prBgdPxls.clear();
    prFgdPxls.clear();

    return iterCount;
}

GCApplication gcapp;

static void on_mouse(int event, int x, int y, int flags, void *param)
{
    gcapp.mouseClick(event, x, y, flags, param);
}

int main(int argc, char **argv)
{
    cv::CommandLineParser parser(argc, argv, "{@input| messi5.jpg |}");
    help(argv);

    string filename = parser.get<string>("@input");
    if (filename.empty())
    {
        cout << "\nDurn, empty filename" << endl;
        return 1;
    }
    Mat image = imread(samples::findFile(filename), IMREAD_COLOR);
    if (image.empty())
    {
        cout << "\n Durn, couldn't read img filename " << filename << endl;
        return 1;
    }

    const string winName = "img";
    namedWindow(winName, WINDOW_AUTOSIZE);
    setMouseCallback(winName, on_mouse, 0);

    gcapp.setImageAndWinName(image, winName);
    gcapp.showImage();

    for (;;)
    {
        char c = (char) waitKey(0);
        switch (c)
        {
            case '\x1b':
                cout << "Exiting ..." << endl;
                goto exit_main;
            case 'r':
                cout << endl;
                gcapp.reset();
                gcapp.showImage();
                break;
            case 'n':
                int iterCount = gcapp.getIterCount();
                cout << "<" << iterCount << "... ";
                int newIterCount = gcapp.nextIter();
                if (newIterCount > iterCount)
                {
                    gcapp.showImage();
                    cout << iterCount << ">" << endl;
                } else
                    cout << "rect must be determined>" << endl;
                break;
        }
    }

    exit_main:
    destroyWindow(winName);
    return 0;
}
